CVE-2026-44559

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, the GET /api/v1/channels/{id}/members endpoint only checks membership for group and dm channel types (lines 467-469). For standard channels — including private ones — there is no channel_has_access check before returning the member list. Any authenticated user who knows a private channel’s UUID can enumerate all users with access to that channel. This vulnerability is fixed in 0.9.0.

More information : https://github.com/open-webui/open-webui/security/advisories/GHSA-c7wp-3qh5-55pv